Building a Cedar-Strip Solo Canoe: The Perils and Pitfalls
The title says “Perils and Pitfalls” but it is not the daunting task that those words make it seem. I have built two kayaks and two canoes using the cedar strip/fiberglass cloth/epoxy construction technique and I use them all.
But I began this latest task because I thought I needed a solo canoe. On my last solo wilderness paddling adventure and my last canoe camping fishing trip, my kayaks and canoes were feeling a little heavy to carry on the portages. They range in weight from about 57 to 70 pounds. I decided I needed a light boat for future solo trips, under 45 pounds if possible, and I wanted to try to save on the material cost.
In this article I will walk through most of the major steps in building this canoe and try to offer tips or advice on how it could have been done better.
I Downloaded a Plan
In the spirit of keeping my expenses minimal, I looked for free plans. I found a solo canoe plan, the Northwest Passage Solo Canoe, and downloaded the plans here. I printed the downloaded plans on 8-1/2 by 11 paper then taped together.These plans were for a 15-ft canoe; I planned to shorten it a bit. The plans were for a canoe 25-1/2” wide at the gunwales with a maximum beam of 29 inches. Being narrow at the gunwales and wider at the water line is called tumblehome.
I was trying to save, and the plans worked out, but The large amount of tumblehome, and my decision to shorten the boat made attaching strips more difficult for me, so perhaps stick to the plans. I was skeptical about the plans' accuracy. If you have the same concern, then perhaps purchased plans are a better option; check out the plans at Ashes, for example.
The Build Table ("Strongback")
I reused the table I had from previous builds, but put it on saw horses instead of making legs.
TIP: The build table is usually made in two 8-foot sections which can cause a little sag in the center if you are not careful. Any sag will affect the shape of the hull, and in this case the rocker (a slight curvature of the bottom from bow to stern which makes the boat more maneuverable). I added some support and checked the levelness afterwards.
Making the Plywood Forms
I gathered as much scrap plywood as I could find around home to make the forms. I only purchased one ½ sheet. Next I cut the plans at the outermost hull line and traced onto the plywood. Then I cut the next lower hull line and so on. I traced the stems onto cardboard, using a pin poked thru the plans along the stem lines to mark the outline on the cardboard. I then cut the forms to shape with a jig saw and smoothed the edges with a wood rasp.
TIP: Scrap plywood worked but it requires more careful set up due to its varying thickness. I would recommend using plywood of all the same thickness.
Mounting the Forms
I screwed 2x2 mounting blocks onto the table so the plywood forms would be on roughly 12-inch centers. Since I was shortening the boat, I used 11½ inches instead of 12, to get about a 14’4” boat. When I attached the forms I used C-clamps to hold them to the blocks until I could check the straightness and fairness of the hull shape. I ran a piece of Dacron fishing line from the bow to stern form to help with alignment. I used a long cedar strip laid at various places along the forms and sighted along the edge to see it the forms lined up. Once satisfied, I screwed the forms to the blocks and attached the long strip to all the forms to hold them perpendicular to the table, which I checked with a square. Before attaching the strips I covered the form edges with plastic packing tape to keep the strips from becoming glued to the plywood.
TIP: This step is critical to ensure a smooth looking hull. I didn’t take enough time on it, and about halfway through attaching the strips, I found some problems with alignment. This resulted in a hull with a flat spot where it shouldn’t have been, and it required me to build up the forms with layers of masking tape where the gaps between the strips and the plywood were too large. I also had to unscrew two forms and shift their positions. Perhaps a better way to check the shape of the hull would be to stretch some plastic sheeting over the hull and staple it on temporarily, or just leave on instead of taping the form edges.
A Stemless Design
All of my other boats were built using laminated stems, an inner and outer. This provided a place to attach the strip ends and some more rugged protection for the leading edge of the bow and stern. This design was stemless, since I wanted to save weight. This required shaping the stem forms and covering them with plastic tape.
TIP: Shaping the stems so the strips lay flat is important. The angle is sharper toward the gunwales and flattens out toward the bottom. It takes a little patience using a wood rasp.
Cutting the Strips
I purchased all my wood from a big box store (Menards). It allowed me to sort through the piles and pick out what I wanted, mostly knot free, straight and having interesting color variations. I chose mostly red cedar. I used about 30% pine since it was cheaper than cedar and would give me some of the accents I wanted.
All the strips were 10 foot in length. I cut them on a table saw using a Freud Diablo thin curf 40 tooth 7-1/4 blade. They were about 0.2” thick (traditionally 0.25). Next I used a router table to put a bead and cove joint on each strip. There was a fair amount of breakage around knots so I cut extra strips.
TIP: When cutting the strips with a table saw I always get some strips that vary in thickness. NEXT TIME—if there is a next time—I will cut the strips a little thicker then run them through a thickness planer to get consistent strips. This will save a lot of time when planing and sanding the hull. Also—NEXT TIME—I will skip the bead and cove and do “rolling bevel”. This is where a plane is use to make the strip edges fit together uniformly along the length of the boat. I think this will minimize gaps. Check out this Robo-bevel tool by Nick Schade.
Attaching the Strips
I started attaching the strips near the table (near gunwales) and worked my way up the side to the boat's bottom. The first strip was not bent up to the peak of the bow and stern. It had just a slight droop leaving space near the ends of the boat that had to be filled with shorter strips. I stapled the strips on cove side up to hold the glue. The boat was 14+ feet long and the strips only 10 feet so where they joined I used a simple butt joint.
I attached about 3 strips at a time until I got to the bilge where the hull curves, then I attached only one at a time. This was only done when the temperatures were above 57°F (Titebond III can work down to 55°F). Then I allowed the glue to dry overnight.
Where the strips come together at the bow and stern, I used an alternating pattern was used. I stapled one strip was stapled to the end form (stem) and the strip on the opposite side was held in place above the attached strip and cut with a pull saw using the beveled end form as a guide. I then glued and clamped the ends. I used a sort of herring bone pattern with the strip ends on the bottom. When it was time to close the flat bottom of the hull with strips I used a straight pattern rather than stripping one side and cutting along the center line.
TIP: The shape of the hull caused a lot of twisting in the strips making it difficult. The joints where short strips meet can be tricky and require creative clamping methods. Putting glue in a cheap condiment bottle from the grocery store made dispensing glue easier.
I started the boat thinking I would use no staples and rely just on clamps but grew impatient and hauled out the staple gun. After each round of strips is stapled (or clamped) on, I pressed them together looking for glue to ooze out, then taped them together with masking tape. I tried to make a fancy feature strip using small diamond-shaped pieces of wood and dowels. It was a disaster and I gave up on that idea. Instead I used the natural contrast in the wood strips to make a more subtle, and I think, attractive, pattern. If you have the room, lay the strips out flat to find a nice contrasting pattern, then number them.
Shaping and Sanding the Hull
After all the staples were pulled, I found some large gaps that needed patching, so I filled them with epoxy thickened with sanding dust. Then I used a sure-form plane, block plane, mini-block plane, and various grits of sand paper on a random orbital sander to smooth the hull. The planes were used to take down the high spots and 50 grit sandpaper was used to shape the hull. Then came another round of gap filling. The next-to-the-last sanding was with 80- then 100-grit sandpaper, then I wet the hull and let it dry. Then I used 120-grit sand paper.
TIP: Sanding and shaping takes a long time, especially with the crude strips I had. I found that, although tiresome, sanding by hand was more effective. You have to be careful using heavy grit and a power sander. I sanded through the hull in one spot where I had a little bulge. It required building up the inside with a lot of thickened epoxy patching.
When sanding dust is added to epoxy for patching, it always dries a little darker than the surrounding wood. Be careful to use clean sanding dust. Mine came from a shop vac attached to my ROS. I hosed the vacuum tub out before I used it but it had some dust in the vacuum hose from when I’d used it to clean my chimney. A little black soot can make your patch turn very dark.
I found that it’s best not to over-do sanding when trying to remove the darker color. When the whole boat is covered with unthickened epoxy and cloth, most of the dark spots blend in.
Care should be taken with the sure -orm plane. It can leave deep scratches that are hard to sand out. Lots of good lighting is helpful for this step, and the whole project.
This step will be repeated on the inside after the outside fiberglass and epoxy is finished. It’s better if all the hull is perfectly smooth, but you have to decide what is good enough. The inside is difficult to make perfectly smooth. The cloth will conform to a piece-wise shape if you are careful. On my later boats I can feel the flat surface of a lot of strips.
Making the Gunwales
I made the outer gunwales from mahogany and the inner from maple. Since the boards I used were only 8-footers, the outer gunwales (3/4x5/8 inch) were cut with a scarf joint at a angle cut line of about 8 times the gunwale thickness. They were glued with thickened epoxy. The inner gunwales (3/4X3/8 inch) were scarf joined in two places since I didn’t have long enough boards. Scuppers (openings in the interior gunwales for water drainage when the canoe is flipped over) were made by gluing on (with thickened epoxy) spacers made from scrap pieces of cedar stripping three inches long and two inches apart. The ends of the spacers were beveled using a sanding drum bit in a drill press.
I made some small decks from scrap cherry and attached them at the bow and stern using thickened epoxy and brass screws. The inside gunnels were mortised into the decks and attached to the hull with a few brass screws and, you guess it, thickened epoxy, then clamped all over. The edge of the hull was left a little proud of the gunwale. After the inside gunwale glue had cured I attached the outer with epoxy and screws. The screws were recessed into hole I drilled with a forstner bit the covered with a piece of dowel glued in place. When outside gunwale was set up I added some extra thickness to the inside gunwale with piece of cedar strip in the area where the seat and thwart were going to be mounted. When all has cured for a few days I planed, sanded and shaped the gunwales and decks.
TIP: I found a C-clamp hung over the edge of the hull helps hold the long gunwales sort of in place while you are trying to attach them.
Try to remove the excess epoxy glue before it dries, especially under the gunwales. Some say that screws are not needed for the gunnels but I felt more comfortable using them. Also it makes installation a little easier. The hull should be roughed up with sandpaper before the gunwales are glued on.
If your boat design has a lot of curve fore and aft, It may be necessary to pre-bend the gunwales with steam and/or water soak by clamping to a jig. This should be done before the scupper spacers are glued on. Alternatively the scuppers could be a routed channel in the inner gunwale. I did that on my first boat but experience some chip out.
Making the Thwart and the Seat and Carry Handles
I made the seat frame from 2 steam bent ¼” thick maple and one ¼” thick redwood laminations. The redwood came from an old hot tub I scrapped out.
I decided to cane the seat as shown in this article. It was attached to the inside gunnels with three inch long spacers and ¼”x 5" stainless carriage bolts and wing nuts with washers. The gunwales are at a slight angle so I recessed one side of the bolt heads with a 5/8” forstner bit.
The thwart is just a straight piece made from maple and cherry, and I gave a little extra thickness with redwood. It was attached with lock washers, nuts and brass screws counter sunk into the inside gunwale.
At each end is a maple-and-redwood carry handle about 4 inches from the deck, attached with brass screws and epoxy.
TIP: Caning is tedious. It is easy to make mistakes and takes a long time. But it looks cool. I stained the seat wood and wished I had not; the center redwood lamination is almost invisible. Trying to drill a hole through the 3 -nch spacers and make it centered at each end was tough. I decided to drill a pilot hole in each end, and then and oversized hole half way through from each end. That way, if it was off center that fact would be hidden inside where the holes meet.
I was originally planning to attach the seat with cleats glued to the side of the hull, and make it adjustable fore and aft, but decided not to, on advice from other builders. I laid the seat on top of the gunnels to make the length it needed to be, but after I cut it found it could have been a little wide due to the flare out in the hull.
The seat has about a 1-inch drop in the middle so it is lower to the floor, giving the canoe a bit more stability. I measured the placement of the seat and thwart based on the plans I had for a 13-foot solo canoe from Ashes Stillwater Boats, then I scaled it for the 14'4" length. The thwart I made is probably a little more heavy duty than it needs to be.
Making Flotation Panels
At each end of the canoe is a panel made of strips, fiberglass cloth and epoxy on both sides. I laid a strip at an angle from the floor to the underside of each deck then hot melt glued thin strips of wood to it so they touched the hull and formed the shape of the panel. I cut the panel to shape and dry fit it in place marking the hull. Then I attached a piece of foam weather stripping about ¼” behind the marked line to help hold the panel in place while I filled gaps with thickened epoxy trying to make a fillet. Once the epoxy set, I put in some 3 inch wide strips of fiberglass cloth with resin around the edges to tie the panel to the hull.
TIP: The flotation panel helps cover up a rough-looking inside stem joint. It also does help your canoe from partially sinking, although I didn’t calculate the volume I needed, just guessed. I should have taken a little more care, some of the gaps that needed to be filled were too large. The panels could be fitted with a hatch like I did on another boat.
Varnishing the Hull
The entire hull needs to be protected with a marine or exterior spar varnish. This protects the epoxy from degradation due to UV light. The bare wood also needs to be sealed. For the interior I used 3-4 coats (1 quart) of Varathane exterior spar gloss varnish (to save some money, it was about $12 a quart). For the exterior I used the same amount of System 3 Marine Spar Gloss Varnish. I sealed the bare wood (gunwales, decks, seat spacers, thwart) with Varathane mixed 50/50 with mineral spirits. I used a foam brush and bristle brush for these applications
TIP: The foam brush wears out quickly but puts down a nice coating. If it is warm I found that thinning the varnish allows it to flow better. If it is too hot, the varnish wants to clump and dry before it levels out. The varnish should be given a few weeks to cure before the boat is used. When the smell is gone, it's probably ready.
Time and Material
The total material cost, not including shipping, sales tax and most tools, was about $525. It took about 120 hours to build. It weighs 45 pounds.
Launching the Canoe
I found that the canoe seemed a little tippy at first, but the secondary stability seemed good; if I leaned it, it felt that it would take some effort to tip. The canoe was fast and maneuverable, and tracked well.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.